Carburetor



Vvuu v Feb. 16, 1932. c. E. MANNING GARBURETOR Filed March 7, 1923 2 Sheets-Sheet 26L GAS & LIQLHD CONTACT APPARATUS.

. Feb-16, 1932. c. E MANNING CARBURETOR Filed March '7, 1923 2 Sheets-Sheet 2 NW flmx (Y Q N MW I w w w w/ \m L 1 \W J 1, M/J/ x 4' J wk 1 N u I. m 5: ,W m w xi .v AWEFRN wil %N GAS 8L LlOUlD CONTACT APPARATUS.

Patented Feb. 16, 1932 UNITED STATES PATENT OFFICE CLARENCE E. MANNING, 0F FLINT, MICHIGAN, ASSIGNOR TO JACOB RICHARD FRANCIS, OF FLINT, MICHIGAN CARIBURETOR Application filed March 7, 1923. Serial No. 623,431.

This invention relates to certain new and same to the intake of an internal combustion useful improvements in carburetors and more particularly to carburetors of the Marvel type in which a low speed nozzle is employed and a high speed nozzle over which 'is arranged a suction controlled valve, the object being to provide means for controlling the supply of fuel delivered to the high speed nozzle; actuated by the movement of the throttle valve so that at any determined range of speed, the flow of fuel to the high speed nozzle may be calibrated to deliver a predetermined amount of fuel to the mixing chamber.

Another and further object of the invention is to provide novel means for controlling the supply of fuel delivered to the high speed nozzle so that the fuel supply can be metered between the high speed nozzle and source of supply by the movement of the throttle.

A still further object of the invention is to provide a. construction of carburetor with metering means which is exceedingly simple and cheap in construction and one which is capable of being used in connection with various constructions of carburetors, the parts being so mounted that a positive metering action is obtained by the movement of the throttle.

Other and further objects and advantages of theinvention will be hereinafter set forth and the novel features thereof defined by the appended claims.

In the drawings,

Figure lis an enlarged side elevation partly in section showing my improved construction of metering pin;

Figure 2 is a vertical section through a carburetor constructed in accordance with my invention; and

Figure 3 is a detail side elevation partly in section showing the use of a slightly modified form ofmetering pin and operating me ans.

In the drawings I have shown a Marvel type of carburetor comprising a body 1 having a tubular bore 2 provided with a lateral air inlet 3 at its lower end and provided with means at its upper end for connecting the engine.

The lower end of the bore is closed by an insert 4 having a fuel passage 5 leading from the fuel bowl 6 which is provided with the usual float for maintaining a predetermined level of fuel therein. The insert is provided with an air passage 7 having a venturi 8 into which extends a low speed nozzle 9 controlled by a needle valve 10, said nozzle being in communication with the fuel passage 5.

Extending upwardly from the insert 4 is a high speed nozzle 11 over which is arranged a pivoted suction controlled valve 12, the opening movement of which is retarded by a spring 13 mounted in an adjusting screw 14, said valve carrying a plunger 16 connected to the spring as clearly shown so that the opening movement of the suction controlled valve is resisted by the tension of the spring. The upper end of the bore is provided with a throttle valve 17 carried by a shaft 18. The above description is given so that the operation of my improved construction of metering means when attached to this type of carburetor can be clearly understood.

The fuel passage 5 formed in the insert is provided with a branch 18 which extends into a housing 20 formed integral with the insert and is in communication with the chamber 21 of a plug 22 mounted therein as clearly shown in dotted lines in Figure 1, said plug being provided with a bore 22 at its lower end. The lower end of the housing 20 is closed by a plug 23 and extending from one side of the housing is a fuel passage 24 which is in communication with the high speed nozzle 11 so that fuel will be supplied from the fuel bowl to the high speed nozzle.

The upper end of the housing 20 is internally threaded and in which is secured the threaded reduced end of a housing 25 provided with a chamber 26 and a reduced bore 27 forming a bearing. Slidably mounted within the bearing formed by the bore 27 is a metering pin 28 which is provided with an annular reduced portion 29 adjacent its lower end working through the bore 22 formed in the lower end of the plug 22 and is provided with a washer 30 under which is arranged a 3..

coil spring 31 for normally holding the pin in raised osition.

The re uced portion 29 of the metering pin 28 forms an enlarged head 29 at its lower end which is slightly less in diameter than the bore 22' so as to allow a predetermined amount of fuel to always pass around the head in order to supply the high speed nozzle with a predetermined amount of fuel at all times. The reduced portion of the metering pin is of such a size that when the metering pin is in the position shown in Figure 1, the space around the same in the bore 22' is suifi- ":ient to supply the high speed nozzle with a redetermined amount of fuel. By this construction, at intermediate speed the high speed nozzle is supplied with a minimum amount of fuel and at high speed a maximum amount.

Formed integral with the body of the carburetor above the housing 25 is a boss 32 in which is slidably mounted a pin 33 provided with a head 34 at its lower end adapted to rest on the upper end of the metering pin 28 when said pin is held in raised position by the spring so as to raise the operating pin in position to be engaged by the cam of the throttle as will be later described.

Secured on the shaft 18 of the throttle valve 17 is a lever 35 for operating the same having a cam 36 which is adapted to engage the upper end of the pin 33 when the throttle valve is moved into any predetermined open position so that upon the movement of the throttle, the pin 33 is engaged by the cam 36 and forced downwardly which pin forces the metering pin 28 downwardly in order to change the size of the passage around the outlet of the plug to increase the supply to the high speed nozzle.

In the modified form of metering pin shown in Figure 3, the shaft 18 of the throttle valve 17 is provided with a throttle valve lever 35 for operating the throttle in the usual manner, said lever being provided with an arm 36 which is adapted to engage the upper end of the pin 33 which is mounted in the boss 32 when the throttle is moved into any predetermined open position.

Mounted within the bore 27 of the housing is a metering pin 28 which is provided with a reduced tapering end 29 working through the bore 22' formed in the end of the plug 22 and the tapering portion of the pin is of such a size that when the pin is in raised position a predetermined quantity of fuel will be allowed to pass through the bore of the plug into the fuel passage 24 which is in communication with the high speed nozzle and the calibration of the nozzle is such that the quantity of fuel supplied at intermediate speed is less than the size of the nozzle so that when the suction controlled "alve opens at high speed, an additional amount of fuel will be delivered to the mixing chamber.

In this form, as the throttle valve is opened, the arm carried thereby forces the metering pin 28 downwardly so as to change the size of the passage of the plug around the variable portion of the metering pin in order to allow an additional amount of fuel to flow to the high speed nozzle so that a gradual additional supply of fuel is delivered to the high speed nozzle as the throttle valve is moved into open position.

While I have shown a metering pin constructed in this particular manner, I do not wish to limit myself to the details of construction as I am aware that various changes can be made without departing from the spirit of my invention which consists in providing a carburetor with a high speed nozzle arranged under a suction controlled valve and supplied with a predetermined quantity of fuel at intermediate speed which accumulates in the nozzle when the suction controlled valve is closed and which quantity of fuel may be either gradually increased from a predetermined movement of the throttle or increased at one time to supply the full capacity of the fuel to the high speed nozzle in order to supply an additional amount of fuel to the charge forming device at high speed.

While I have shown a carburetor constructed in a particular manner to obtain this result, I am aware that various changes in the manner of constructing the metering pin and the carburetor itself can be made without departing from the spirit of my invention as defined by the claims.

From the foregoing description it will be seen that I have provided a carburetor with a high and low speed nozzle, the high speed nozzle being arranged under a suction controlled valve in such a manner that it is not brought into operation until the suction is suiiicient to raise the valve against the tension of the spring, at which time the high speed nozzle delivers fuel to the mixing chamber of the charge forming device, which quantity of fuel is increased at high speed by the final opening movement of the throttle valve so as to deliver an additional amount of fuel to the charge forming device at high speed, the maximum amount being delivered when the throttle is in full open position.

It will also be seen that in my construction of carburetor the high speed nozzle is acted on by the suction so as to draw the fuel supplied thereto out of the nozzle as the suction controlled valve opens, which supply is varied when the throttle valve is moved towards open position, whereby the maximum amount of fuel supplied by the high speed nozzle will be at wide open position and the minimum amount at any predetermined intermediate throttle position whereby I am able to cover a wide range with an internal combustion engine provided with a carburetor constructed in accordance with my invention, as the 28!. GAS & LIQUlU CONTAC T APPARATue.

engine can be throttled down to two or three miles per hour and the speed increased to or miles per hour, the proper explosive mixture being delivered to the engine at every speed by supplying additional fuel to increase the richness of the mixture in proportion to the air supplied at high speed.

\Vhat I claim is 1. A carburetor comprising a body having a bore provided with a throttle valve at its upper end and an air inlet at its lower end, high and low speed nozzles arranged within said bore, a pivoted suction controlled valve arranged over said high speed nozzle, means for retarding the movement of said suction controlled valve, means for supplying fuel to said high and low speed nozzles and a metering pin operated by the movement of the throttle for metering the amount of fuel delivered to the high speed nozzle at the source of supply, said metering pin being adapted to deliver a minimum amount of fuel to said high speed nozzle at intermediate speed and a maximum amount of fuel at high speed.

2. A carburetor comprising a body having a bore provided with a lateral air inlet at its lower end and a throttle valve for closing its upper end, an insert for closing the lower end of said bore, fuel nozzles carried by said insert, a fuel bowl, fuel passages leading from said fuel bowl to said nozzles, a suction controlled valve arranged over one of said nozzles, means for controlling the passage of fuel through the other nozzle and means for controlling at the source of supply the fuel delivered to the first mentioned nozzle, said means comprising a metering pin operated by the movement of the throttle, said metering pin being adapted to deliver a minimum amount of fuel to said high speed nozzle at intermediate speed and a maximum amount of fuel at high speed.

3. A carburetor comprising a body having a bore provided with a lateral air inlet at its lower end and a throttle valve at its upper end, a pivoted suction controlled valve mounted in said bore, a high speed nozzle arranged in said bore and terminating adjacent the free end of said suction controlled valve, a. low speed nozzle spaced from said high speed nozzle. a fuel bowl for delivering fuel to said nozzles, a metering pin for controlling the flow of fuel to said high speed nozzle, said metering pin being arranged to allow a minimum amount of fuel to pass to said high speed nozzle at intermediate speeds and movable by means operated by the throttle to allow a maximum amount of fuel at high speed.

4. A carburetor comprising a body provided with a mixing chamber having a throttle controlled outlet, high and low speed nozzles arranged in said body, a suction controlled valve arranged over the high speed yuan VI.

nozzle, a fuel bowl for delivering fuel to said nozzle, fuel passages leading from said fuel bowl to said nozzles, a plug arranged in the fuel passage of the high speed nozzle, a metering pin working through said plug and means operated by the movement of the throttle for adjusting said metering pin to deliver a minimum amount of fuel to said high speed nozzle at intermediate speed and a maximum amount of fuel at high speed.

5. A carburetor comprising a body having a mixing chamber provided with a throttle controlled outlet, high and low speed nozzles arranged within said body, a pivoted suction controlled valve arranged over the high speed nozzle, adjustable means for resisting the opening movement of said suction controlled valve, a housing carried by said body provided with an apertured plug having a chamber with an opening in its bottom, a fuel bowl, said last-mentioned chamher being in communication with said fuel bowl and said high speed nozzle, a metering pin extending through said aperture of the plug and having portions of varyin sizes for regulating the quantity of fuel delivered to the high speed nozzle and means operated by the movement of the throttle for increasing the supply of fuel passing to the high speed nozzle.

6. A carburetor comprising a body having a mixing chamber provided with a throttle controlled outlet, high and low speed nozzles for delivering fuel to said mixing chamher, a suction controlled valve -arranged over said high speed nozzle, a fuel bowl, a housing in communication with said fuel bowl and said high speed nozzle, a metering pin for controlling the passage of fuel through said housing to said high speed nozzle, means operated by the movement of the throttle for changing the position of said metering pin within said housing whereby said metering pin will deliver a minimum amount of fuel to said nozzle at intermediate speed and the maximum amount of fuel to said nozzle at high speed.

7. A carburetor having high and low speed nozzles, a suction controlled valve arranged over the high speed nozzle, means for supplying fuel to said high and low speed nozzles and means for metering the supply of fuel to the high speed nozzle at the source of supply, said means comprising a throttle-operated metering pin adapted to deliver a minimum amount of fuel to said high speed nozzle at intermediate speed and a maximum amount of fuel to said high speed nozzle at high speed.

8. A carburetor having high and low speed nozzles, a suction controlled valve for con trolling the passage of fuel through said high speed nozzle, means for supplying fuel to said high and low speed nozzles, and means controlled by the position of the throttle valve for metering the supply of fuel to the high speed nozzle, said means being adapted to deliver a minimum amount of fuel to said high speed nozzle at intermediate s eed and a maximum amount of fuel to said high speed nozzle at high speed.

9. A carburetor having high and low speed nozzles,-a suction controlled valve arranged over said high speed nozzle, means for supplying and maintaining fuel at a predetermined level in said nozzles and means controlled by the position of the throttle valve for metering the supply of fuel to the high speed nozzle, said means being adapted to deliver a minimum amount of fuel to said high speed nozzle at intermediate speed and a maximum amount of fuel to said high speed nozzle at high speed.

10. A carburetor having high and low speed nozzles, a suction controlled valve for controlling the passage of fuel through said high speed nozzle, means for supplying fuel to said high and low speed nozzles, and means for metering the supply of fuel to said high speed nozzle, said means comprising a throttle operated metering pin adapted to deliver a minimum amount of fuel to said high speed nozzle at intermediate speed and a maximum amount of fuel to said high speed nozzle at high speed.

11. A carburetor having high and low speed nozzles terminating in different horizontal planes, means for supplying and maintaining fuel at a predetermined level in said nozzles, a suction controlled valve arranged over said'high speed nozzle, means for metering the supply of fuel to said high speed nozzle, said means comprising a throttle operated metering pin adapted to deliver a min imum amount of fuel to said high speed nozzle at intermediate speed and a maximum amount of fuel to said high speed nozzle at high speed. i

12. A carburetor for internal combustion engines having a mixing chamber provided with air inlets, high and low speed nozzles arranged in said air inlets, a suction controlled valve for closing one of said air inlets and means controlled by the position of the throttle valve for metering the supply of fuel to the high speed nozzle, said means being adapted to deliver a minimum amount of fuel to said high speed nozzle at intermediate speed and a maximum amount of fuel to said high speed nozzle at high speed.

In testimony whereof I hereunto aflix my signature.

CLARENCE E. MANNING. 

